@@ -36,7 +36,7 @@ sgx_epc_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
backend->aligned = true;
name = object_get_canonical_path(OBJECT(backend));
- ram_flags = (backend->share ? RAM_SHARED : 0) | RAM_PROTECTED;
+ ram_flags = (backend->share ? RAM_SHARED : RAM_PRIVATE) | RAM_PROTECTED;
return memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), name,
backend->size, ram_flags, fd, 0, errp);
}
@@ -82,7 +82,7 @@ file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
backend->aligned = true;
name = host_memory_backend_get_name(backend);
- ram_flags = backend->share ? RAM_SHARED : 0;
+ ram_flags = backend->share ? RAM_SHARED : RAM_PRIVATE;
ram_flags |= fb->readonly ? RAM_READONLY_FD : 0;
ram_flags |= fb->rom == ON_OFF_AUTO_ON ? RAM_READONLY : 0;
ram_flags |= backend->reserve ? 0 : RAM_NORESERVE;
@@ -52,7 +52,7 @@ memfd_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
backend->aligned = true;
name = host_memory_backend_get_name(backend);
- ram_flags = backend->share ? RAM_SHARED : 0;
+ ram_flags = backend->share ? RAM_SHARED : RAM_PRIVATE;
ram_flags |= backend->reserve ? 0 : RAM_NORESERVE;
ram_flags |= backend->guest_memfd ? RAM_GUEST_MEMFD : 0;
return memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), name,
@@ -28,7 +28,7 @@ ram_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
}
name = host_memory_backend_get_name(backend);
- ram_flags = backend->share ? RAM_SHARED : 0;
+ ram_flags = backend->share ? RAM_SHARED : RAM_PRIVATE;
ram_flags |= backend->reserve ? 0 : RAM_NORESERVE;
ram_flags |= backend->guest_memfd ? RAM_GUEST_MEMFD : 0;
return memory_region_init_ram_flags_nomigrate(&backend->mr, OBJECT(backend),
@@ -246,6 +246,16 @@ typedef struct IOMMUTLBEvent {
/* RAM can be private that has kvm guest memfd backend */
#define RAM_GUEST_MEMFD (1 << 12)
+/*
+ * In RAMBlock creation functions, if MAP_SHARED is 0 in the flags parameter,
+ * the implementation may still create a shared mapping if other conditions
+ * require it. Callers who specifically want a private mapping, eg objects
+ * specified by the user, must pass RAM_PRIVATE.
+ * After RAMBlock creation, MAP_SHARED in the block's flags indicates whether
+ * the block is shared or private, and MAP_PRIVATE is omitted.
+ */
+#define RAM_PRIVATE (1 << 13)
+
static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn,
IOMMUNotifierFlag flags,
hwaddr start, hwaddr end,
@@ -1952,7 +1952,11 @@ RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, ram_addr_t max_size,
ERRP_GUARD();
RAMBlock *new_block;
Error *local_err = NULL;
- int64_t file_size, file_align;
+ int64_t file_size, file_align, share_flags;
+
+ share_flags = ram_flags & (RAM_PRIVATE | RAM_SHARED);
+ assert(share_flags != (RAM_SHARED | RAM_PRIVATE));
+ ram_flags &= ~RAM_PRIVATE;
/* Just support these ram flags by now. */
assert((ram_flags & ~(RAM_SHARED | RAM_PMEM | RAM_NORESERVE |
@@ -2095,7 +2099,11 @@ RAMBlock *qemu_ram_alloc_internal(ram_addr_t size, ram_addr_t max_size,
{
RAMBlock *new_block;
Error *local_err = NULL;
- int align;
+ int align, share_flags;
+
+ share_flags = ram_flags & (RAM_PRIVATE | RAM_SHARED);
+ assert(share_flags != (RAM_SHARED | RAM_PRIVATE));
+ ram_flags &= ~RAM_PRIVATE;
assert((ram_flags & ~(RAM_SHARED | RAM_RESIZEABLE | RAM_PREALLOC |
RAM_NORESERVE | RAM_GUEST_MEMFD)) == 0);
@@ -2170,7 +2178,8 @@ RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
RAMBlock *qemu_ram_alloc(ram_addr_t size, uint32_t ram_flags,
MemoryRegion *mr, Error **errp)
{
- assert((ram_flags & ~(RAM_SHARED | RAM_NORESERVE | RAM_GUEST_MEMFD)) == 0);
+ assert((ram_flags & ~(RAM_SHARED | RAM_NORESERVE | RAM_GUEST_MEMFD |
+ RAM_PRIVATE)) == 0);
return qemu_ram_alloc_internal(size, size, NULL, NULL, ram_flags, mr, errp);
}